Benjamin s



B. S. HARBAOH.

METHOD OF AMALGAMATING.

NITED STATES PATENT rrrcn.

BENJAMIN s. HARBACH, OF'PHILADELPHIA, PENNSYLVANIA.

METHOD OF AMALGAMATING.

SPECIFICATION forming part of Letters Patent No. 340,504, dated April20, 1886.

Application filed August 3, 1885. Serial No. 173,411.

To all whom it may concern:

Be it known that I, BENJAMIN S. HARBAOH, a citizen of the United States,residing at Philadelphia, in the county of Philadelphia. and State ofPennsylvania, have invented certain new and useful Improvements inMethods of Amalgamatiug, of which the following is a specification,reference being had therein to the accompanying drawings.

The object of this invention is to effect a rapid and economicalseparation of gold'from the earth in which it is found without the useof water; and to this end the invention consists in a new method foraccomplishing what is generally known as dry amalgamation, the detailsof which will be hereinafter fully eX- plained.

Figure 1 is a vertical section on line y y, Fig. 2. Fig. 2 is an endelevation. Fig. 3isa transverse section on line a: m, Fig. 1. Fig. 4 isa side elevation. Fig. 5 is a detached view, enlarged, of one of thespirals or convolutions of the conveyer.

Like figures indicate like parts in all the views.

1 1 are the posts, 2 2 the sills, and 3 a cross-girt, of theframe,which, however, may be of any construction adapted to support theoperative parts of my machine.

4 is a cylinder-head at the head end or receiving end of the machine. I

5 6 is the lower half of the cylinder or cas ing, which is semicircularin cross-section and of uniform diameter throughout, except that at itsrear end or discharging end it is contracted, as at 6, (see Figs. 1, 2,4,) whereby the lowerside at its extreme rearend is somewhat elevated,for a purpose which will be explained. I prefer to use a secondsemi-cylinder or shell, 7, which may be hinged to the part 5 6, as at 88.

9 is a half-head closing the discharging end of the machine above thegirt 3.

10 is a shaft mounted in suitable hearings on the frame-workforinstance, as indicated in the drawings-and provided at suitableintervals withspider-arms 11 11, the hubs of which are keyed orotherwise made fast to the shaft.

12 represents the convolutions of aconveyer or worm mounted upon andcarried by the (No model.)

spider-arms, and of an external diameter a little less than the internaldiameter of the shell, so as to revolve in close proximity to saidshell.

13 14 are spider-arms and convolutions at the tail end of the conveyer,and are of such reduced diameter as will correspond substantially to thereduced size of the part 6 of the casing.

15 16 is a trough arranged below the shell, which latter is cut away tocorrespond with the upper edges of the sides of the trough. Bypreference the bottom of this trough is inclined, as indicated in Fig.1.

17 is a feed-hopper, through which the mingled mass of gold, earth, andother materials may be fed into the machine. There may be a supply-pipeopening into the head end of the trough, as at 18, Fig. 1.

19 20 represent, respectively, a dischargepipe and stop-cock or othergate located at the tail end of the trough, through which to draw offits contents, as may be desired.

21 is a transverse partition placed in the trough near the dischargingend of the machine, the lower edge of the partition being a shortdistance above the bottom of the trough, so as to form a throat throughwhich the contents of the trough may pass.

22 is a pulley or band wheel on the end of shaft 10. This pulley may bebelted to any convenient motor.

23 23 are holes-one or more-in the widened rear ends, 16, of thetrough,to permit the passage of air and the overflow of mercury, as willbe explained.

24 is a bracket or saddle, in which the head end or receiving end of theshell 5 6 may be conveniently supported.

I do not wish to be limited to the particular form of conveyer-spiralsshown, nor to arranging them at any particular inclination or pitch, norto making them in a substantially continuous worm or thread, as isindicated, because, under some circumstances, I may find it desirable touse separateoonvolutions, substantially as indicated in Fig. 5.

By an examination of the drawings it will be seen that when the troughis filled with quicksilver its upper surface will be a little above thelower edges of the conveyor-blades,

so that during the revolutions of the conveyer the mingled mass of gold,auriferous earth, and other material will be rolled, tumbled, andthoroughly agitated in such manner that all portions of it will besuccessively brought into contact with the quicksilver, and that thegold will sink to the bottom of the trough, or at least into thequicksilver; but the refuse will be slowly advanced over the surface ofthe quicksilver, and finally discharged at the rear end of the machinewithout seriously disturbing the surface of the quicksilver, or, underordinary circumstances, causing it to bank up in advance of theconveyer-blades.

In order to effectually guard against the quicksilver being advancedfrom the head machine toward the discharging end, I have extended bothsides of the trough beyond the lines atwhich it (the trough) isintersected by the shell or cylinder, into which extensions thequicksilver and such gold as may be accumulated therein can flowtemporarily.

The inclined reduced'portion 6 of the cylinder, while it will notinterfere with the discharge of refuse, will return to the trough anyquicksilver which may possibly be carried thither with the refuse andwould otherwise be discharged and wasted.

In order to guard against any loss or westage by reason of thequicksilver or gold adhering to the conveyer, I make it wholly of ironor other neutral material, whereby I am enabled to accomplish asatisfactory separa tion of the gold from the earth and other impuritiesin a more economical manner than has ever before been attained.

As a further safeguard against the contents of the trough being forcedrearward and out of the machine with the refuse, I provide the partition21, the upper edge of which is on a line with the lower line of theconveyer, the lower edge of the partition being a short distance fromthe bottom of the trough, and through the throat thus formed thequicksilver and port-ions of all of the gold in the trough will passwhen the stopcock 20 is opened.

By slowly introducing a fresh supply ofmercury at 18, and leaving thestop-cock slightly 0 en, a continuous flow of mercury and gold t roughthe trough can be maintained, and the mercury, after the gold has beenseparated therefrom, may be returned and run through the machine again.

Should the mercury from any cause-such as accumulation of gold in thetroughrise above its sidesinto the cylinder, it would not, underordinary cireumstances,rise high enough to be discharged at the tail endwith the refuse, because of the overflow-holes 23, (see Figs. 1 and 4,)thus avoiding thewaste of quicksilver and gold which might otherwiseresult.

Although I regard iron as the best material for the conveyer, yet I donot wish to be limited thereby, because I may use any other materialwhich is neutral-that is to say, to which 1 quicksilver will not adherewhen brought into contact therewith by the operation of the machine.

Of course a hand crank may be used instead of a band-wheel to drive theconveyer.

I am aware of the fact that use has been made of rectilinearly-movingbrushes to carry dry material over mercury, said brushes being arrangedperpendicularly to their path; but I so treat the material that it shallbe turned and tumbled over and over, and the mercury is not pusheddirectly forward as it is by devices similar to the brushes abovementioned. No disturbance of the mercury is caused by theconveyerblades, the latter in my construction difl'ering from thoseconveyers heretofore used in their arrangement relatively to the mercuryand the walls which retain the pulp. Aslow forward movement of theamalgamated material in the trough is facilitated by having the body ofmercury gradually increase in depth, so that the heavier portion cannotreach the bottom at once, but shall be suspended more or less until itreaches the exit. By so arranging the parts that they shall act in thisway I can supply at the upper end fresh mercury, which shall besubstantially proportional to the val nable material delivered to itssurface, and which can be caused to move as a current, eithercontinuously or at such intervals as are advantageous.

By having the mercury-chamber divided into two partsone communicatingwith the other, and one so arranged that the earth shall not be incontact with the mercury thereinI can prevent the mercury from bankingup in 'front of the conveyer at the tail end, as the mercury can escapefrom one part of the chamber to the other, and hence it can be preventedfrom being carried up the incline at the end and lost with the refuse.

By examining Fig. Sit will be seen that l the ore is prevented fromlying stationary to the right and to the left of the bottom central lineof the conveyer, the cylinder or shell above (if the ore-holder) themercury'holder being outside and independent of the bottom walls of thecylinders by the sides of the opening. These walls converge downwardly,and the lower parts partially support the ore and assist thecouveyer-blades in thoroughly rolling and turning the dry material, and,at the same time, in order to reach the entire body of ore, it is notnecessary to have the main body of the mercury disturbed by the conveyer-blades.

By the processes heretofore followed, in the earryingout of which usewas made of conveyers, the greater part of the body of mercury wasdisturbed, or if this was avoided there was a very imperfect advancingof the dry material upon the surface.

One of my aims is to accomplish the thorough agitation of the drymaterial with as lit-' tle agitation as possible of the mercury. Iprefer to carry out my process by means of a mechanism in which themercury-holder is IIQ ardent v constructed and arranged, substantiallyas set forth, to have the upper surface of the mercury wider than theopening or passage between the downwardly-converging walls be 5 low theconveyer, as these walls assist in attaining the end above alluded to-towit, roll ing and agitating the oreand this arrangement provides arecoil-chamber, into which the mercury can readily pass, to prevent itsbankingin front of the conveyer-blades, which I prefer to havemerely-dip through the very surface, but not pass down into the mainbody thereof.

In carrying out my process there is no disturbing the body of themercury, the contact therewith of the extreme edge of thc conveyerbladesbeing only sufficient to assist in disposing of the amalgam as it isformed.

It is a well-known fact in this art that the amalgamating processesheretofore followed cannot be applied to the treatment of a vast amountof material which is known to contain valuable metal, for the reasonthat the loss of the mercury (first through .its amalgamating with themetallic parts of the machinery, and, secondly, from its being carriedout of the apparatus on account of thcgreat agitation and disturbance towhich it is subjected) more than compensates for the gold which isobtained. I have succeeded in overcoming this difliculty by employing aconveyer of iron and treating the material in such way that the oreshall be rolled over and over while the main body of the mercury is, asabove said, left undisturbed, I thus avoid the carrying of any partthereof out with the refuse.

Although I have herein most frequently made mention of the separation ofgold from earth or refuse, &c., yet it will be, of course, understoodthat I do not limit myself to treating that metal only, as the processcan be applied in obtaining any of the metals which are obtained byamalgamating.

Some of the advantages of the process can be obtained if the materialbeadvanced otherwise than by the spiral conveyer-blades shown.

I do not herein claim the novel features incident to the mechanism whichIhave shown, 50 preferring to claim those in another application, No.180,855, filed October 24, 1883, and herein claim only the process whichI have devised. The mechanism shown is notlimited to the process which Ihave herein claimed, as others can be carried out by means thereofas,for instance, the common one employing water for dissolving orsuspending the earth.

WVhat I claim is- 1. The herein -described improvement in the art ofseparating metal from earth or refuse, consisting in moving a mass ofore or refuse in a dry state over a mass of mercury by an iron conveyer,rolling said ore or refuse on lines oblique to the path of advance, andpreserving the main body of the mercury in an undisturbed state,substantially as set forth.

2. The herein-described improvement in the art of separating gold fromrefuse or earth, consisting in moving a mass of ore or refuse in a drystate over an elongated mass of mercury, the ore or refuse being causedto roll while partly supported by stationary walls and partly supportedby the mercury, .the main body of the latter being kept in anundisturbed condition, substantially as set forth.

3. The herein-described improvement in the art of separating gold fromearth or refuse, which consists in rolling a mass of the earth andgoldmingled together in a dry state over a body of mercury ofgradually-increasing depth by a convey er, substantially as set forth.

4. The herein-described improvement in the art of separating gold fromearth or refuse, which consists in moving a mass of mingled materialover a body of mercury by means acting positively and independently ofthe movements of the mercury, and causing said mercury, while the solidmaterial is upon its surface, to flow in a current in the direction ofthe advance of the solid material,and withdrawing the amalgamatedportion from the machine before itcan be returned to the feeding end,substantially as set forth.

In testimony whereof I affix my signature in presence of two witnesses.

BENJAMIN s. HARBAOH.

Witnesses: v CHAS. H. OTTERSON, I. L. SPRooLE.

